The objective of this project is to enable the applicant to continue to participate in three epidemiologic studies in the former German Democratic Republic (GDR) and Czechoslovakia investigating acute and chronic health effects resulting from exposure to environmental contaminants (particularly air pollutants). Three visits of four months duration each are requested; the studies are expected to continue at least through 1999. (1) A study of acute health effects on children and adults of exposure to a number of air pollutants, some at levels rarely seen in the U.S. any more. (2) A large on-going cross-sectional prospective study of the effect on respiratory and allergic disorders in successive cohorts of children and older women in one of the most highly polluted regions in the former GDR. (3) A prospective epidemiologic study of pregnant women and their offspring to determine environmental risk factors for the development of asthma.